.nd-left-panel {
  display: block;
  border-right: 1px solid rgba(0, 0, 0, 0.14);
  bottom: 0;
  background: #fff;
  color: #212121;
  left: 0;
  position: fixed;
  top: 0;
  width: 240px;
  z-index: 4;
  overflow-x: hidden;
  overflow-y: hidden;
  transform: translateZ(0);
  transform-style: preserve-3d;
  transition-delay: 0.1s;
  transition-duration: 0.2s;
  transition-property: transform, left;
  transition-timing-function: cubic-bezier(0.4, 0, 0.2, 1);
  box-shadow: 0 2px 2px 0 rgba(0,0,0,0.14), 0 1px 5px 0 rgba(0,0,0,0.12), 0 3px 1px -2px rgba(0,0,0,0.2);
  
  &:hover {
    overflow-y: auto;
  }
}